printempress
New Member
Hi yall! First post here, woohoo!
It seems that when OBA's in substrates for printing are being discussed, it's in regards to color output, but right now I'm actually wondering if anyone has any experience or knowledge to share regarding ink adhesion on media that might contain OBA's.
I run LED UV flatbed printers within the print dept of a larger manufacturer, and I need to print on a new type of flexible PVC as a component of our latest product. It was found that the ink adhered more strongly on an off-white version of the PVC than the 'whitest' one. An industry colleague who also UV prints onto this PVC has shared the same experience with me. I'm aware that the right primer will solve that issue, but printing on the off-white one will be fine for us, and really I'm writing because I'm curious about this alleged phenomenon in the first place.
I suspect the main difference between the white and off-white PVC is the use of an OBA, but why?
Is the light resistance inherent in the OBA affecting UV ink adhesion? But if it did, wouldn't I just be able to bump up my light to fix that? Or, might it be UV wavelength issues?
The spec sheet for my particular PVC doesn't tell me what OBA they might be using, but after some research, it seems the most likely OBA for a PVC is an oxazole, and note the UV range.
webbook.nist.gov
The second page here compares mercury UV lamp wavelength to a LED UV wavelength.
Is the fact that my light and this added ingredient in my media with differing UV wavelengths be a factor?
Or, do OBA's just cause lower surface tension?
I have personally never needed to print with fluorescent inks or substrates yet, but I have seen a few anecdotes online suggesting others have had greater adhesion issues with those than traditional pigments. This page suggests fluorescent inks/substrates may or may not necessarily technically use an OBA. (Is that correct?..) However, similarly to OBA-containing materials, fluorescent materials also: work by essentially fooling our color perception, degrade over time with UV exposure, and cause viscosity changes.
Interesting advice to minimize printing over fluorescent inks due to adhesion issues!
And a fun little page promoting an OBA, for its low and apparently therefore awesome surface tension!
www.knowde.com
What do yall think??
Thanks!!
It seems that when OBA's in substrates for printing are being discussed, it's in regards to color output, but right now I'm actually wondering if anyone has any experience or knowledge to share regarding ink adhesion on media that might contain OBA's.
I run LED UV flatbed printers within the print dept of a larger manufacturer, and I need to print on a new type of flexible PVC as a component of our latest product. It was found that the ink adhered more strongly on an off-white version of the PVC than the 'whitest' one. An industry colleague who also UV prints onto this PVC has shared the same experience with me. I'm aware that the right primer will solve that issue, but printing on the off-white one will be fine for us, and really I'm writing because I'm curious about this alleged phenomenon in the first place.
I suspect the main difference between the white and off-white PVC is the use of an OBA, but why?
Is the light resistance inherent in the OBA affecting UV ink adhesion? But if it did, wouldn't I just be able to bump up my light to fix that? Or, might it be UV wavelength issues?
The spec sheet for my particular PVC doesn't tell me what OBA they might be using, but after some research, it seems the most likely OBA for a PVC is an oxazole, and note the UV range.
Oxazole
webbook.nist.gov
The second page here compares mercury UV lamp wavelength to a LED UV wavelength.
Is the fact that my light and this added ingredient in my media with differing UV wavelengths be a factor?
Or, do OBA's just cause lower surface tension?
I have personally never needed to print with fluorescent inks or substrates yet, but I have seen a few anecdotes online suggesting others have had greater adhesion issues with those than traditional pigments. This page suggests fluorescent inks/substrates may or may not necessarily technically use an OBA. (Is that correct?..) However, similarly to OBA-containing materials, fluorescent materials also: work by essentially fooling our color perception, degrade over time with UV exposure, and cause viscosity changes.
Interesting advice to minimize printing over fluorescent inks due to adhesion issues!
And a fun little page promoting an OBA, for its low and apparently therefore awesome surface tension!
P.A.T Products - Optical Brightener - Excellent Adhesion - Knowde
Repi OPTICAL BRIGHTENERS is specialized for their function as optical brighteners, redefine excellence in industrial additives and materials. With low
www.knowde.com
What do yall think??
Thanks!!